Violence increased as tensions tipped over into all-out war and UN human rights chief Zeid warned country “on the verge of total collapse”. Saudi Arabia and ten other (mostly Arab, Sunni) countries 26 March launched “operation decisive storm”, countrywide air campaign against Huthis and allied military units loyal to former President Ali Abdullah Saleh; goal is to restore President Hadi’s govt, but operation risks pulling Yemen further into Saudi-Iranian regional struggle, augmenting sectarian divides, closing any hope of negotiated political solution. Political crisis continued to deepen as violence overtook UN-brokered negotiations. Fighting broke out in earnest between Hadi and forces associated with Huthis and former President Saleh in Aden 19 March. Huthis 19-20 March bombed presidential residence in Aden, moved northern military units and other forces southwards. Clashes ongoing between Hadi-aligned groups in Aden, backed by Saudi-led airstrikes, and Huthi/Saleh forces. Over 40 refugees killed in air raid on refugee camp in Haradh area near Saudi border 31 March. Al-Qaeda 18 March assassinated Abulkarim al-Khaywani, journalist and liberal voice within Huthi movement; 20 March captured security and local govt buildings in southern Lahj governorate. Islamic State (IS, formerly ISIL) claimed responsability for 20 March suicide bombings on Zaydi mosques in Sanaa that killed over 130.

Political crisis deepened as Huthis moved to fill void left by late Jan resignation of President Hadi and govt: Huthi leaders 6 Feb announced establishment of revolutionary council, high security committee and parliamentary body charged with electing presidential council. Move triggered immediate international and domestic condemnation: several foreign embassies suspended operations and evacuated diplomats including U.S., EU, UK, France, Germany, Saudi Arabia and UAE; all political parties rejected declaration, anti-Huthi protests grew in Sanaa and central provinces. UNSC 15 Feb called on Huthis to relinquish control of state institutions, release president and ministers from house arrest; GCC countries lobbying for diplomatic isolation argued UNSC resolution should have allowed for enforcement under UN Charter’s Chapter Seven. UN 20 Feb brokered agreement on creating transitional council; President Hadi next day escaped Sanaa for southern city of Aden: issued statement reasserting his authority as president, accusing Huthis of coup d’état and calling on body created to oversee implementation of national dialogue outcomes to meet in Aden or Taiz; fears move could further accelerate conflict, territorial disintegration. Groups in several southern and western governorates declared autonomy from Sanaa, many actively prepared to resist Huthis; battle lines increasingly taking sectarian overtones, pitting Shafai (Sunni) areas against Huthis. Popular committees in Aden, funded by Hadi but with unclear loyalties, 16 Feb clashed with govt Special Security Forces allegedly affiliated with Huthis and/or former President Saleh: seized key areas including city’s port, intelligence HQ and other state buildings. Huthis advanced against al-Qaeda (AQAP) in Baydah province, dozens reported killed 14 Feb; AQAP 12 Feb captured military base in Shebwa province. U.S. drone strikes continued including four killed in Baydah 2 Feb.

Govt and President Hadi 22 Jan resigned, throwing political process established through Sept “Peace and National Partnership Agreement” (PNPA) into question and raising prospect of territorial fragmentation, widespread violence. Move followed push by northern Huthis to take complete control of Sanaa 19-20 Jan: surrounded presidential palace, captured additional military positions and state institutions, put Hadi under virtual house arrest. Presidential resignation awaiting approval by parliament; observers fear Huthis could appoint presidential or military committee without adequate buy-in from other groups, causing violent backlash from Shafai (Sunni) areas and southern separatists. Several anti-Huthi demonstrations in Sanaa late month, including by thousands of protesters 24 Jan. Huthi push triggered by dispute with Hadi over draft constitution, especially proposed federal structure; Huthi fighters 17 Jan kidnapped presidential advisor allegedly seeking to force through six-region federalism without Huthi consent. Insurgent leader Abdul-Malik al-Huthi 20 Jan accused Hadi of obstructing PNPA, indicated willingness to remove president. Hadi next day accepted all Huthi demands in return for advisor’s release, Huthi withdrawal from certain military positions; agreement immediately collapsed as Huthis dictated terms of implementation under threat of military force. Security council of Aden governorate 22 Jan announced it would no longer take orders from Sanaa following Hadi’s resignation. Al-Qaeda in the Arab Peninsula (AQAP) claimed responsibility for 7 Jan attack on satirical magazine Charlie Hebdo in Paris, same day exploded car bomb outside Sanaa police academy killing over 40; observers warned group gaining strength amid Huthi expansion. Six reported killed in U.S. drone strikes late Jan.

Northern Huthis continued expansion, directly challenging President Hadi and authority of new govt, while further galvanising southern calls for independence. Huthis continued push to consolidate power in north: leader Abdulmalik al-Huthi 15 Dec called President Hadi “umbrella for corruption”, demanded Huthis be allowed to oversee state finances. Huthi supporters subsequently tightened control of Sanaa, prevented newly appointed chief of staff from entering defence ministry; 16 Dec dismissed editor of main state news outlet; 17 Dec stormed Central Bank, Civil Status and Registration building and nationally owned Safer oil company. PM Bahah same day threatened to resign along with rest of govt. Parliament 18 Dec passed vote of confidence in favour of govt. Huthis mid-month seized northern city Arhab, stronghold of Sunni Islamist party Islah, after intense clashes; tightened control over strategic Red Sea port of Hodeidah, including dismissing governor and port facility director. Clashes between Huthis and al-Qaeda (AQAP) militants continued in Baydah province’s Radaa city; dozens killed in car bombings targeting Huthis 16 Dec, including fifteen schoolgirls. Suicide bomber 31 Dec killed dozens at Huthi-organised religious celebration in Ibb city. Independence protests continued in south; army 15 Dec killed separatist leader in Aden city. American and South African hostage held by AQAP killed along with at least eleven others during U.S. rescue attempt 6 Dec in Shebwa province; AQAP blamed deaths on U.S., launched attack on air force base outside Aden known for support of U.S. drone operations. Saudi Arabia continued withholding aid due to Huthi expansion, raising fears of impending govt financial collapse.

Clashes between Huthis and al-Qaeda (AQAP)-allied tribesmen continued in central Baydah province: hundreds, possibly thousands, reported killed. Huthis continued advancing, 19 Nov seized AQAP stronghold Radaa city, pushed toward predominantly Sunni Marib governorate containing significant part of country’s oil reserves. Marib tribesmen warned against Huthi advances, pledged to destroy oil and electricity infrastructure if Huthis sought to occupy facilities, causing fears of more clashes, economic damage and growing sectarian tensions. Southern pro-independence demonstrations continued; protesters maintained 30 Nov deadline for all northern govt personnel to leave south. UNSC 7 Nov issued sanctions against former president Saleh and two Huthi commanders; announcement galvanised opposition against govt and president Hadi from Saleh’s General People’s Congress (GPC) party; GPC announced opposition to new cabinet sworn in by Hadi 9 Nov, removed Hadi from party leadership. Economic crisis deepened following Saudi Arabia’s reported halt of direct financial assistance to govt in response to Sept Huthi takeover of Sanaa; fears declining reserves could render govt unable to cover salaries, imports in coming months. At least seven reported killed in U.S. drone strike 12 Nov in southern Shabwa province.

Huthi fighters continued to advance following mid-Sept seizure of Sanaa, bringing country’s political transition to brink of collapse despite nominal political process established through late Sept UN-brokered peace and power-sharing agreement. Huthis consolidated power in north, took control of large parts of Red Sea Coast including strategic port of Hodeidah 14 Oct; met with little resistance, at times facilitation, from govt and local population. Huthi expansion into central provinces met with resistance from supporters of Sunni Islamist party Islah, Ansar al-Sharia affiliates and al-Qaeda (AQAP); hundreds reported killed including over 250 in Baydah province. AQAP 9 Oct killed at least 47 in suicide attack targeting Huthi gathering in Sanaa. Huthis continued working with military and police to secure Sanaa, raided homes and offices of political enemies; supporters acted as shadow govt overseeing decisions of cabinet ministers. President Hadi 26 Oct criticized Huthi expansion, called for withdrawal from newly acquired territories including Sanaa. Hadi 13 Oct appointed broadly accepted candidate for PM, country’s UN representative Khalid Bahah, following criticism of previous nominee by Huthis and General People’s Congress; new cabinet yet to be formed. Huthis 31 Oct held tribal gathering in Sanaa, gave Hadi 10-day deadline to form govt. Southern separatists renewed call for independence, tens of thousands demonstrated in Aden and Mukullah 14 Oct; movement’s representatives gave govt until 30 Nov to remove all employees and security forces from south, demanded international oil companies halt exports until revenues redirected to new southern state.

Weeks of Huthi-led anti-govt protests in Sanaa degenerated into several days of fighting mid-month between Huthis and rival forces loyal to General Ali Mohsen al-Ahmar and Sunni Islamist party Islah; over 200 killed, Huthis captured Mohsen-affiliated military camp, al-Iman University and nearby state TV station. Large parts of security forces sided with Huthis, allowing group to control govt buildings and security in city. New peace deal and power sharing agreement signed 21 Sept calling for implementation of national dialogue outcomes including govt inclusive of all groups, anti-corruption measures, timeline for disarmament of non-state actors; accord seen as favouring Huthis to detriment of other stakeholders, particularly Islah. Peace deal called for Huthis to withdraw from capital, replacement of govt; President Hadi has not yet appointed new premier. Prospects for Huthi withdrawal uncertain despite peace deal ending major combat in Sanaa: Huthis surrounded and entered homes of political enemies following agreement, 27 Sept attacked home of national security chief Ali al-Ahmadi. Widespread fears of retaliatory attacks against Huthis and govt, particularly from al-Qaeda (AQ); at least 20 reported killed in separate AQ attacks targeting Huthis 28 Sept.

Month saw mass Huthi-organised protests in Sanaa against govt's late July lifting of fuel subsidies, including rallies of tens of thousands starting 18 Aug demanding new govt, lower fuel prices; reports armed Huthi supporters gathered around Sanaa. Govt 23 Aug offered resignation within month and formation of economic committee to evaluate subsidies; Huthi leaders rejected offer, reemphasised demands including strengthening authority of body charged with overseeing national dialogue implementation, greater inclusion of Huthis in state institutions. President Hadi late month supported counter rallies largely attended by Sunni Islamist Islah party; hundreds of thousands reportedly rallied across country 29 Aug. Protests underscored growing political polarisation between pro-and anti-Huthi factions: some framed protests as real revolution, others as Iranian-inspired religious coup. Violence continued between Huthis and various adversaries in far north including in Jawf; at least 2 cease- fires collapsed during month. Scores reported killed in clashes between govt forces and al-Qaeda (AQAP) affiliates in southern Hadramout province; militants 8 Aug provoked widespread public anger by killing 14 unarmed soldiers in retaliation for govt strikes. AQAP leadership mid-month praised recent gains by jihadi group Islamic State (IS; formerly ISIL or ISIS) in Iraq without pledging allegiance to IS leader Abu Bakr al- Baghdadi.

Clashes in north between Houthis and rival tribes, army units intensified early month: hundreds killed, tens of thousands displaced. Houthi fighters 8 July captured Amran city north of Sanaa, including military base of 310th brigade, aligned with Islah party and General Ali Mohsen al-Ahmar; air force bombed Houthi positions. Houthis agreed to return Amran to govt control following pressure from President Hadi, along with UNSC, U.S., EU and GCC; tensions remained high, skirmishes continued in surrounding areas. Tribal militants continued to attack critical energy infrastructure crippling oil exports, causing lengthy electricity blackouts in Sanaa. Govt 30 July lifted diesel subsides prompting scattered pro- tests. Alleged al-Qaeda affiliates continued assassination campaign against security personnel in south; at least 2 soldiers, 6 militants reported killed in car bombings, clashes in Abyan 27 July.

Yemen’s transition is gradually unravelling amid unprecedented security and economic challenges partly caused by political infighting and weak consensus on national dialogue results. Violence between Huthis and army spiked when air force early June bombed Huthi positions as they advanced toward Sanaa; 100 Huthis, 20 govt forces reported killed 2 June; hundreds killed in north throughout month. UN brokered ceasefire agreement 4 June: agreement lacked national power-sharing arrangement with Huthis, plan for implementing gradual disarmament; fighting later resumed. Another ceasefire announced 22 June but never implemented. Military campaign against al- Qaeda (AQAP) continued at slower pace; govt raids, U.S. drone strikes met with sporadic retaliatory attacks, mostly against security forces. Economic crisis worsened: govt almost unable to pay salaries causing fears of unrest; tribal sabotage of electrical grid early June left Sanaa without fuel or electricity for days prompting mass protests 11 June calling for overthrow of govt. President Hadi same day announced cabinet reshuffle; failed to replace politically divisive PM Basindawa or bring new groups into govt. Govt forces mid-month surrounded Sanaa’s Saleh mosque on suspicion premises being used by former President Saleh to stage coup.